/* =============================================
   TIC TAC TOE — CYBERPUNK NEON EDITION
   ============================================= */

/* ---- DESIGN TOKENS ---- */
:root {
  --font-display: 'Orbitron', monospace;
  --font-body: 'Rajdhani', sans-serif;
  --radius: 1rem;
  --radius-sm: 0.5rem;
  --radius-pill: 2rem;
  --transition: 0.25s ease;
}

/* ---- DARK THEME (default) ---- */
.dark {
  --bg:              #07070f;
  --bg-glow-a:       rgba(0, 229, 255, 0.055);
  --bg-glow-b:       rgba(255, 32, 121, 0.055);
  --surface:         rgba(255, 255, 255, 0.042);
  --surface-hover:   rgba(255, 255, 255, 0.08);
  --border:          rgba(255, 255, 255, 0.08);
  --border-x:        rgba(0, 229, 255, 0.35);
  --border-o:        rgba(255, 32, 121, 0.35);
  --text:            #c8d8f0;
  --text-dim:        rgba(200, 216, 240, 0.38);
  --x-color:         #00e5ff;
  --x-glow:          rgba(0, 229, 255, 0.55);
  --o-color:         #ff2079;
  --o-glow:          rgba(255, 32, 121, 0.55);
  --win-stroke:      #ffd700;
  --win-glow:        rgba(255, 215, 0, 0.65);
  --draw-color:      #8899bb;
  --shadow:          0 24px 64px rgba(0, 0, 0, 0.65);
  --cell-line:       rgba(255, 255, 255, 0.07);
  --btn-gradient:    linear-gradient(135deg, #00bcd4, #0055ff);
  --btn-hover-glow:  0 6px 24px rgba(0, 100, 255, 0.35);
  --overlay-bg:      rgba(7, 7, 15, 0.82);
}

/* ---- LIGHT THEME ---- */
.light {
  --bg:              #eef2ff;
  --bg-glow-a:       rgba(0, 100, 255, 0.07);
  --bg-glow-b:       rgba(200, 0, 140, 0.055);
  --surface:         rgba(255, 255, 255, 0.72);
  --surface-hover:   rgba(255, 255, 255, 0.92);
  --border:          rgba(0, 0, 0, 0.09);
  --border-x:        rgba(0, 110, 255, 0.35);
  --border-o:        rgba(220, 0, 90, 0.35);
  --text:            #111530;
  --text-dim:        rgba(17, 21, 48, 0.38);
  --x-color:         #005ce6;
  --x-glow:          rgba(0, 92, 230, 0.4);
  --o-color:         #d6004e;
  --o-glow:          rgba(214, 0, 78, 0.4);
  --win-stroke:      #ff8800;
  --win-glow:        rgba(255, 136, 0, 0.55);
  --draw-color:      #7788aa;
  --shadow:          0 16px 48px rgba(0, 0, 80, 0.12);
  --cell-line:       rgba(0, 0, 0, 0.07);
  --btn-gradient:    linear-gradient(135deg, #0066cc, #4400dd);
  --btn-hover-glow:  0 6px 24px rgba(0, 60, 200, 0.3);
  --overlay-bg:      rgba(238, 242, 255, 0.82);
}

/* =============================================
   RESET & BASE
   ============================================= */
*, *::before, *::after {
  margin: 0; padding: 0;
  box-sizing: border-box;
}

html { font-size: 16px; -webkit-tap-highlight-color: transparent; }

body {
  min-height: 100vh;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-body);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background var(--transition), color var(--transition);
  overflow-x: hidden;
}

/* ambient gradient orbs */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 55% at 18% 15%, var(--bg-glow-a), transparent),
    radial-gradient(ellipse 55% 50% at 82% 85%, var(--bg-glow-b), transparent);
  pointer-events: none;
  z-index: 0;
}

/* subtle scanline texture (dark only) */
.dark body::after,
.dark::after {
  content: '';
  position: fixed;
  inset: 0;
  background-image: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(0, 0, 0, 0.03) 2px,
    rgba(0, 0, 0, 0.03) 4px
  );
  pointer-events: none;
  z-index: 0;
}

/* =============================================
   GLASSMORPHISM UTILITY
   ============================================= */
.glass {
  background: var(--surface);
  backdrop-filter: blur(22px);
  -webkit-backdrop-filter: blur(22px);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}

/* =============================================
   THEME TOGGLE
   ============================================= */
.theme-toggle {
  position: fixed;
  top: 1.1rem; right: 1.1rem;
  z-index: 200;
  width: 2.6rem; height: 2.6rem;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--surface);
  backdrop-filter: blur(14px);
  font-size: 1.05rem;
  cursor: pointer;
  display: flex; align-items: center; justify-content: center;
  transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1), background var(--transition);
  color: var(--text);
}
.theme-toggle:hover { transform: rotate(25deg) scale(1.12); }

/* =============================================
   APP SHELL
   ============================================= */
.app {
  position: relative; z-index: 1;
  display: flex; flex-direction: column; align-items: center;
  gap: 1.15rem;
  padding: 1.6rem 1rem 2rem;
  width: 100%; max-width: 460px;
}

/* =============================================
   TITLE
   ============================================= */
.title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 7vw, 3rem);
  font-weight: 900;
  letter-spacing: 0.12em;
  line-height: 1;
  color: var(--text);
}
.title span {
  color: var(--x-color);
  text-shadow: 0 0 22px var(--x-glow), 0 0 60px var(--x-glow);
}

/* =============================================
   SCOREBOARD
   ============================================= */
.scoreboard {
  display: flex;
  border-radius: var(--radius);
  overflow: hidden;
  width: 100%;
}

.score-item {
  flex: 1;
  display: flex; flex-direction: column; align-items: center;
  padding: 0.8rem 0.5rem;
  gap: 0.15rem;
  transition: background var(--transition);
}
.score-item + .score-item { border-left: 1px solid var(--border); }

.score-mark {
  font-family: var(--font-display);
  font-size: 1.35rem; font-weight: 700; line-height: 1;
}
.x-color  { color: var(--x-color); text-shadow: 0 0 10px var(--x-glow); }
.o-color  { color: var(--o-color); text-shadow: 0 0 10px var(--o-glow); }
.draw-color { color: var(--draw-color); }

.score-value {
  font-family: var(--font-display);
  font-size: 1.9rem; font-weight: 900;
  transition: transform 0.2s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.score-value.bump {
  animation: scoreBump 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
}
@keyframes scoreBump {
  0%   { transform: scale(1); }
  50%  { transform: scale(1.45); }
  100% { transform: scale(1); }
}

.score-name {
  font-size: 0.62rem; font-weight: 600;
  text-transform: uppercase; letter-spacing: 0.07em;
  color: var(--text-dim);
}

/* =============================================
   MODE SELECTOR
   ============================================= */
.mode-selector {
  display: flex; gap: 0;
  border-radius: var(--radius);
  overflow: hidden;
  padding: 0.28rem;
  width: 100%;
}

.mode-btn {
  flex: 1;
  padding: 0.6rem 0.75rem;
  border: none; border-radius: var(--radius-sm);
  background: transparent; color: var(--text);
  font-family: var(--font-body); font-size: 0.88rem; font-weight: 600;
  cursor: pointer; letter-spacing: 0.03em;
  transition: all 0.22s;
}
.mode-btn.active {
  background: var(--btn-gradient);
  color: #fff;
  box-shadow: var(--btn-hover-glow);
}
.mode-btn:not(.active):hover { background: var(--surface-hover); }

/* =============================================
   DIFFICULTY SELECTOR
   ============================================= */
.difficulty-selector {
  display: flex; gap: 0.5rem;
  width: 100%;
  animation: fadeSlideIn 0.3s ease;
}
@keyframes fadeSlideIn {
  from { opacity: 0; transform: translateY(-6px); }
  to   { opacity: 1; transform: translateY(0); }
}

.diff-btn {
  flex: 1;
  padding: 0.48rem 0.5rem;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: transparent; color: var(--text-dim);
  font-family: var(--font-body); font-size: 0.78rem; font-weight: 700;
  cursor: pointer; text-transform: uppercase; letter-spacing: 0.06em;
  transition: all 0.22s;
}
.diff-btn:not(.active):hover {
  border-color: var(--border-x); color: var(--text);
}
.diff-btn.active {
  border-color: var(--x-color); color: var(--x-color);
  background: rgba(0, 229, 255, 0.07);
  box-shadow: 0 0 12px rgba(0, 229, 255, 0.18);
}

/* =============================================
   TURN INDICATOR
   ============================================= */
.turn-indicator {
  font-family: var(--font-body);
  font-size: 0.92rem; font-weight: 600; letter-spacing: 0.06em;
  padding: 0.42rem 1.2rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border);
  background: var(--surface);
  backdrop-filter: blur(12px);
  transition: border-color 0.3s, box-shadow 0.3s;
}
.turn-indicator.x-turn {
  border-color: var(--border-x);
  box-shadow: 0 0 14px rgba(0, 229, 255, 0.1);
}
.turn-indicator.o-turn {
  border-color: var(--border-o);
  box-shadow: 0 0 14px rgba(255, 32, 121, 0.1);
}

/* =============================================
   BOARD
   ============================================= */
.board-container {
  position: relative;
  width:  min(88vw, 360px);
  height: min(88vw, 360px);
}

.board {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  grid-template-rows: repeat(3, 1fr);
  width: 100%; height: 100%;
  background: var(--surface);
  backdrop-filter: blur(22px);
  -webkit-backdrop-filter: blur(22px);
  border: 1px solid var(--border);
  border-radius: 1.4rem;
  overflow: hidden;
  box-shadow: var(--shadow);
}

/* Grid inner lines */
.cell { border-right: 1px solid var(--cell-line); border-bottom: 1px solid var(--cell-line); }
.cell:nth-child(3)  { border-right: none; }
.cell:nth-child(6)  { border-right: none; }
.cell:nth-child(9)  { border-right: none; border-bottom: none; }
.cell:nth-child(7)  { border-bottom: none; }
.cell:nth-child(8)  { border-bottom: none; }

.cell {
  position: relative;
  display: flex; align-items: center; justify-content: center;
  cursor: pointer;
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 11vw, 4.2rem);
  font-weight: 900;
  background: transparent;
  user-select: none;
  -webkit-user-select: none;
  transition: background 0.18s;
  overflow: hidden;
}

/* ripple on hover */
.cell:not(.x):not(.o)::before {
  content: '';
  position: absolute; inset: 0;
  background: radial-gradient(circle at var(--mx, 50%) var(--my, 50%),
    rgba(255,255,255,0.06) 0%, transparent 70%);
  opacity: 0;
  transition: opacity 0.2s;
}
.cell:not(.x):not(.o):hover::before { opacity: 1; }
.cell:not(.x):not(.o):hover { background: var(--surface-hover); }

/* X mark */
.cell.x {
  color: var(--x-color);
  text-shadow: 0 0 18px var(--x-glow), 0 0 36px var(--x-glow);
  cursor: default;
}
/* O mark */
.cell.o {
  color: var(--o-color);
  text-shadow: 0 0 18px var(--o-glow), 0 0 36px var(--o-glow);
  cursor: default;
}

/* Place animation */
.cell.placed {
  animation: placeMark 0.3s cubic-bezier(0.34, 1.56, 0.64, 1) forwards;
}
@keyframes placeMark {
  0%   { transform: scale(0) rotate(-15deg); opacity: 0; }
  65%  { transform: scale(1.18) rotate(4deg); opacity: 1; }
  100% { transform: scale(1) rotate(0); }
}

/* Winning cell pulse */
.cell.winning { animation: winPulse 0.7s ease-in-out infinite alternate; }
.cell.x.winning { background: rgba(0, 229, 255, 0.08); }
.cell.o.winning { background: rgba(255, 32, 121, 0.08); }
@keyframes winPulse {
  from { filter: brightness(1); }
  to   { filter: brightness(1.5) saturate(1.3); }
}

/* AI thinking indicator */
.cell.ai-thinking {
  animation: aiPulse 0.6s ease-in-out infinite alternate;
}
@keyframes aiPulse {
  from { background: rgba(255,255,255,0.01); }
  to   { background: rgba(255,255,255,0.04); }
}

/* =============================================
   WIN LINE SVG
   ============================================= */
.win-line {
  position: absolute;
  inset: 0;
  width: 100%; height: 100%;
  pointer-events: none;
  opacity: 0;
  transition: opacity 0.15s;
  overflow: visible;
}
.win-line.visible { opacity: 1; }

.win-line line {
  stroke: var(--win-stroke);
  stroke-width: 5;
  stroke-linecap: round;
  filter: drop-shadow(0 0 8px var(--win-glow)) drop-shadow(0 0 18px var(--win-glow));
}
@keyframes drawLine {
  to { stroke-dashoffset: 0; }
}

/* =============================================
   ACTIONS
   ============================================= */
.actions {
  display: flex; flex-direction: column; align-items: center;
  gap: 0.65rem;
}

.reset-btn {
  padding: 0.72rem 2.2rem;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text);
  font-family: var(--font-body); font-size: 0.9rem; font-weight: 700;
  letter-spacing: 0.06em; text-transform: uppercase;
  cursor: pointer;
  transition: all 0.22s;
}
.reset-btn:hover {
  background: var(--surface-hover);
  border-color: var(--border-x);
  transform: translateY(-2px);
  box-shadow: 0 8px 22px rgba(0,0,0,0.22);
}
.reset-btn:active { transform: translateY(0); }

.clear-btn {
  background: none; border: none;
  color: var(--text-dim); font-family: var(--font-body);
  font-size: 0.72rem; font-weight: 600; letter-spacing: 0.04em;
  cursor: pointer; text-decoration: underline; text-underline-offset: 3px;
  transition: color 0.2s;
}
.clear-btn:hover { color: var(--text); }

/* =============================================
   OVERLAY
   ============================================= */
.overlay {
  position: fixed; inset: 0; z-index: 100;
  background: var(--overlay-bg);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  display: flex; align-items: center; justify-content: center;
  opacity: 0; pointer-events: none;
  transition: opacity 0.3s;
}
.overlay.visible { opacity: 1; pointer-events: all; }

.result-card {
  border-radius: 1.6rem;
  padding: 2.6rem 2.2rem;
  text-align: center;
  min-width: 270px; max-width: 340px; width: 90%;
  display: flex; flex-direction: column; align-items: center; gap: 0.7rem;
  animation: cardIn 0.42s cubic-bezier(0.34, 1.56, 0.64, 1);
}
@keyframes cardIn {
  from { transform: translateY(32px) scale(0.88); opacity: 0; }
  to   { transform: translateY(0) scale(1); opacity: 1; }
}

.result-icon {
  font-family: var(--font-display);
  font-size: 4.5rem; font-weight: 900; line-height: 1;
  margin-bottom: 0.3rem;
}
.result-icon.x { color: var(--x-color); text-shadow: 0 0 28px var(--x-glow); }
.result-icon.o { color: var(--o-color); text-shadow: 0 0 28px var(--o-glow); }
.result-icon.draw { color: var(--draw-color); }

.result-title {
  font-family: var(--font-display);
  font-size: 1.45rem; font-weight: 700;
}
.result-subtitle {
  color: var(--text-dim); font-size: 0.9rem; font-weight: 500;
}

.play-again-btn {
  margin-top: 0.75rem;
  padding: 0.78rem 2.6rem;
  border: none; border-radius: var(--radius-pill);
  background: var(--btn-gradient); color: #fff;
  font-family: var(--font-body); font-size: 1rem; font-weight: 700;
  letter-spacing: 0.06em; text-transform: uppercase;
  cursor: pointer;
  transition: all 0.22s;
  box-shadow: var(--btn-hover-glow);
}
.play-again-btn:hover {
  transform: translateY(-3px);
  filter: brightness(1.1);
  box-shadow: 0 12px 32px rgba(0, 80, 255, 0.45);
}
.play-again-btn:active { transform: translateY(0); }

/* =============================================
   RESPONSIVE
   ============================================= */
@media (max-width: 380px) {
  .app         { gap: 0.9rem; padding: 1rem 0.6rem 1.5rem; }
  .title       { font-size: 1.75rem; }
  .score-value { font-size: 1.55rem; }
  .board-container { width: 94vw; height: 94vw; }
}

@media (min-height: 800px) {
  .app { gap: 1.35rem; }
}

@media (min-width: 520px) {
  .board-container { width: 360px; height: 360px; }
}